PhonicsGame_master/pages/index/index.wxss

.container {
  background-color: #1E1E1E;
  justify-content: flex-start;
} 

.line{
  width: 100%;
  height:30rpx;
  background-color: #00214C;
  position: fixed;
  top:0;
}

.line2{
  width: 100%;
  height:30rpx;
  background-color: #1E1E1E;
  margin-bottom: 30rpx;
}

.btn {
  height:350rpx;
  width:710rpx;
  margin-bottom: 20rpx;
}

.bottom{
  font-size:20rpx;
  color:#fff;
  text-align: center;
  margin: 60rpx 0 40rpx 0;
}